One of the biggest difficulty in estimating the infiltration capacity is the variability of soill conductivity and the difficulty in measuring it. We found that the conductivity is scale dependent and if we measure it from small soil samples the measured value can vary more than 100 times even for samples taken very close to each other. On the other hand the field conductivity measured with large scale field experiments are consistent, but value is dependent on method we use to estimate.
For example the double ring method we use to create a one dimensional flow requires a very large outer cylinder, almost 2m in diameter for high conductivity soils. So we adopted borehole test.